London Offshore Consultants

DP marine Operations

growing operability but at what risk

by Capt. Rutger Bierman

1. Introduction to Dynamic Positioning

2. In the earlier years

3. Industry guidance and DP classes

4. Advantage and wide use of DP

5. Disadvantage and risks of DP

6. Risk Management through DP Assurance

OVERVIEW OF PRESENTATION

Dynamic Positioning (DP)

• A system which automatically controls a vessel’s position

and heading exclusively by means of active thrusts

Dynamic Positioning (DP) System

• The complete installation necessary for dynamically

positioning a vessel

• A complete DP System comprises a power system,

thruster system and the DP-control system

INTRODUCTION TO DP

INTRODUCTION TO DP

INTRODUCTION TO DP

INTRODUCTION TO DP

Environment sensors

Wind sensor

Vertical reference

Gyro

Power generation

Shaft generators

Generator

switchboards

UPS

Power management

system

DP Operator

Human Machine

Interface (HMI)

DP Controller

Position reference

systems

DGPS, laser,

microwave, taut wire,

HPR

Propulsion system

Tunnel thrusters

Azimuth thrusters

CPP and rudders

An Overview of all systems involved in DP

INTRODUCTION TO DP

Industry bodies

INTRODUCTION TO DP

• Cuss 1 - 1961

Joystick control and acoustic

transponders

• Eureka - 1961

Using 3 analog controllers and

taut wire

IN THE EARLIER YEARS

• SEDCO 455 - 1971

built for Shell, it was the first DP

drillship to use a riser and blow out

preventer (BOP) for oil well drilling

• STEPHANITURM - 1978

First purpose build Diving

Support Vessel, specially to

recover gold from HMS

EDINBURGH

IN THE EARLIER YEARS

• In 1980, there were 65 DP

vessels

• Number of DP vessels grew

to 150 in 1985

• In 2011 the number of DP

vessels operating in the

world reached 2000.

• Numbers still increasing

with more specialized

vessels.

IN THE EARLIER YEARS

With growth came the need of Industry guidance.

The most recognized industry bodies are:

• International Maritime Organization (IMO)

• International Marine Contractors Association (IMCA)

• The Marine Technology Society (MTS)

• Class Societies Rules (ABS, DNV, LR, BV)

INDUSTRY GUIDANCE AND DP CLASSES

IMO Circular 645 – June 1994

Guidelines For Vessels With Dynamic Positioning Systems

• Defines redundancy for DP Equipment Class 1, 2 and 3.

• IMCA adopted IMO Circular 645 in full under IMCA M-113.

• Most Class and Flag States requirements for DP Systems

are based on IMO Guidelines as a minimum.

• Charterers requirements are based on IMO Guidelines.

INDUSTRY GUIDANCE AND DP CLASSES

CLASS 1 No redundancy

in equipments

Loss of position

occurs in the event

of a single failure

CLASS 2

Achieved through

redundancy

in equipments

Loss of position should not

occurs in the event

of a single failure

CLASS 3

Achieved through

redundancy in

equipments and

compartment segregation

Loss of position should not

occur in the event of a single

fault including a completely

burnt fire division or flooded

watertight compartment

INDUSTRY GUIDANCE AND DP CLASSES

ADVANTAGE AND WIDE USE OF DP

Advantage of using DP positioned vessels

• No tugs and anchor handling vessels required.

• Quick and easy location set-up.

• Excellent maneuverability.

• Rapid response to change in environmental conditions.

• Rapid response to changes in requirements of operations.

• Ability to work in any water depth.

• Avoid risks of damaging seabed hardware from mooring

lines, anchors or spud cans.

• Avoid complex cross-mooring arrangements with vessels or

fixed structures.

ADVANTAGE AND WIDE USE OF DP

ADVANTAGE AND WIDE USE OF DP

DISADVANTAGE AND RISKS OF DP OPERATIONS

Disadvantage of using DP positioned vessels

• High capital and operational expenditure.

• Higher fuel consumption.

• Might loose position during extreme weather.

• A breakdown of a small part can effect the function of the DP

system.

• Over reliance on the DP System.

• Prone to human error.

DISADVANTAGE AND RISKS OF DP OPERATIONS

SIMOPS

DISADVANTAGE AND RISKS OF DP OPERATIONS

SIMOPS

DISADVANTAGE AND RISKS OF DP OPERATIONS

Close proximity operations

DISADVANTAGE AND RISKS OF DP OPERATIONS

Mumbai High

In average 75 DP incidents are reported to IMCA yearly of

which about half are for have a loss of position

Related Issues:

• DP computer or software issues

• Loss of power plant

• Loss of environmental sensors

• Loss of position reference systems

• Loss of propulsion

• Environmental conditions

• Human error

DISADVANTAGE AND RISKS OF DP OPERATIONS

*Learning the lessons, Reporting DP Incidents by Ian C. Giddings IMCA

DISADVANTAGE AND RISKS OF DP OPERATIONS

RISK MANAGEMENT THROUGH DP ASSURANCE

DP Assurance Process:

• Documentation and Procedures review

• DP Vessel Assurance Process

• DP Personnel Competence Assessment

Documentation and Procedures for Review:

• Failure Mode And Effect Analysis (FMEA)

• Vessel Specific Operations Manual

• DP Checklists

• DP Capability plots

• DP Footprint records

• Master/Chief Engineer standing orders for DP Operations

• Company guidance for DP Operations

• Activity Specific Operating Guidelines (ASOG)

RISK MANAGEMENT THROUGH DP ASSURANCE

RISK MANAGEMENT THROUGH DP ASSURANCE

RISK MANAGEMENT THROUGH DP ASSURANCE

DP Vessel Assurance Process:

• Condition and Suitability Survey

• IMCA Common Marine Inspection Document (CMID)

• OCIMF Offshore Vessel Inspection Questionnaire (OVIQ)

To be checked:

• As build systems and redundancy in relation to FMEA.

• Annual DP trials and FMEA proving trials records.

• DP Footprints taken.

• Planned Maintenance on DP system.

• DP unusual event and DP incident records.

• Check Work history.

RISK MANAGEMENT THROUGH DP ASSURANCE

RISK MANAGEMENT

DP Personnel Competence Assurance:

• CV’s DP Operators, Marine Engineers and ETO.

• DP Log Books and Training Certificates.

(As per IMO circular 738 / IMCA M117)

• DP Familiarization Program on board.

• Interview DP personnel on knowledge of the Vessel, FMEA

and Company Policies.

• Records of DP Emergency Drills carried out.

RISK MANAGEMENT THROUGH DP ASSURANCE

RISK MANAGEMENT

DP Assurance provide a thorough assessment of the

readiness of the vessel, DP system, DP operational

procedures and manning.

The DP Assurance process can be captured in one report.

All deficiencies identified during the DP Assurance survey can

be captured in one register, which makes it easy to track the

close out of these deficiencies for vessel owners, charters and

oil majors.

RISK MANAGEMENT THROUGH DP ASSURANCE

RISK MANAGEMENT

Further Risk Management control would be the use of

a 3rd party for:

• MTS GAP Analysis on FMEA.

• Witnessing of Mobilization or Field Arrival trials.

• Preparation of ASOG.

• Monitoring of DP System upgrades.

• Lessons learned from DP Incident Investigation.

RISK MANAGEMENT THROUGH DP ASSURANCE

END OF PRESENTATION

Thank you